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kennyadapter

@bestucan hhhh谢谢您，我发现我哪里错了，我画网格的时候是xoz面上的，正确的应该是在xoy画个2D的网格，然后openfoam会在z轴增加一个面。

kennyadapter

各位大佬们，我最近才开始接触ICEM，从网上找到一个画圆柱绕流网格的视频，一步一步跟着在ICEM上画了网格：
但是把msh文件导入到open foam中，用

fluentMeshToFoam fluent.msh

命令后，出现了一个问题：

然后我自己又画了一个方形网格，没有圆柱的：

导入到openfoam中，通过paraview查看发现：

只导入了这么一片。大家有没有遇到这个问题啊。我知道openfoam的2D算例本质上是三维的，但是我看youtube上的视频也是画了一层啊。不是是版本问题啊？有大佬可以指导一下我吗？
我参考的视频网址是这个：https://www.bilibili.com/video/BV1ME411A73k?from=search&seid=13841040651016471334
youtube上的一个视频跟他的步骤也差不多的。所以我也么看出是哪里的问题。
还有一点我ansys是18.2版本只安装的时候只安装了ICEM模块，其他的都没安装（是不是这个问题啊。。。）。求助各位大佬了

kennyadapter

@cfd_fly 您好，，有时间可以再分享一下嘛？非常感谢

kennyadapter

请问您解决了吗
我的数据也波动很大

kennyadapter

@东岳在 200万网格管道流qDNS并行算力测试中说：

东岳老师，那怎么调整带宽呢？有什么方法，或者需要更换什么配件吗？

kennyadapter

@东岳
这是我44核心的log文件的最后几个时间步：之前的迭代次数也差不多：


Time = 9.8

Courant Number mean: 0.733368 max: 1.27353
GAMG:  Solving for p, Initial residual = 0.0998056, Final residual = 0.00082233, No Iterations 6
time step continuity errors : sum local = 4.80691e-07, global = 1.99762e-20, cumulative = 1.59798e-17
Pressure gradient source: uncorrected Ubar = 0.1335, pressure gradient = 0.000123775
GAMG:  Solving for p, Initial residual = 0.0809999, Final residual = 0.000584259, No Iterations 6
time step continuity errors : sum local = 3.45394e-07, global = 5.63939e-20, cumulative = 1.60362e-17
Pressure gradient source: uncorrected Ubar = 0.1335, pressure gradient = 0.000120435
GAMG:  Solving for p, Initial residual = 0.0189678, Final residual = 9.4483e-07, No Iterations 39
time step continuity errors : sum local = 5.51633e-10, global = 3.45318e-20, cumulative = 1.60707e-17
Pressure gradient source: uncorrected Ubar = 0.1335, pressure gradient = 0.000119638
ExecutionTime = 170.51 s  ClockTime = 171 s

Time = 9.9

Courant Number mean: 0.73339 max: 1.27886
GAMG:  Solving for p, Initial residual = 0.100098, Final residual = 0.000824461, No Iterations 6
time step continuity errors : sum local = 4.82558e-07, global = 8.66441e-20, cumulative = 1.61574e-17
Pressure gradient source: uncorrected Ubar = 0.1335, pressure gradient = 0.000123823
GAMG:  Solving for p, Initial residual = 0.0809731, Final residual = 0.000577791, No Iterations 6
time step continuity errors : sum local = 3.42103e-07, global = 4.07868e-20, cumulative = 1.61981e-17
Pressure gradient source: uncorrected Ubar = 0.1335, pressure gradient = 0.000120471
GAMG:  Solving for p, Initial residual = 0.0189619, Final residual = 9.31189e-07, No Iterations 39
time step continuity errors : sum local = 5.44568e-10, global = 7.2382e-20, cumulative = 1.62705e-17
Pressure gradient source: uncorrected Ubar = 0.1335, pressure gradient = 0.000119674
ExecutionTime = 172.22 s  ClockTime = 172 s

Time = 10

Courant Number mean: 0.733413 max: 1.27933
GAMG:  Solving for p, Initial residual = 0.0999699, Final residual = 0.000818608, No Iterations 6
time step continuity errors : sum local = 4.79761e-07, global = 8.13808e-20, cumulative = 1.63519e-17
Pressure gradient source: uncorrected Ubar = 0.1335, pressure gradient = 0.00012387
GAMG:  Solving for p, Initial residual = 0.081007, Final residual = 0.000576888, No Iterations 6
time step continuity errors : sum local = 3.41793e-07, global = 5.45899e-20, cumulative = 1.64065e-17
Pressure gradient source: uncorrected Ubar = 0.1335, pressure gradient = 0.000120508
GAMG:  Solving for p, Initial residual = 0.0189675, Final residual = 9.02577e-07, No Iterations 39
time step continuity errors : sum local = 5.28191e-10, global = 1.77208e-20, cumulative = 1.64242e-17
Pressure gradient source: uncorrected Ubar = 0.1335, pressure gradient = 0.00011971
ExecutionTime = 173.99 s  ClockTime = 174 s

End

这是我32核心的：


Time = 9.8

Courant Number mean: 0.733369 max: 1.27363
GAMG:  Solving for p, Initial residual = 0.0998053, Final residual = 0.000728134, No Iterations 6
time step continuity errors : sum local = 4.26347e-07, global = 1.16708e-20, cumulative = 5.86486e-18
Pressure gradient source: uncorrected Ubar = 0.1335, pressure gradient = 0.000123776
GAMG:  Solving for p, Initial residual = 0.0810209, Final residual = 0.00054928, No Iterations 6
time step continuity errors : sum local = 3.24835e-07, global = 4.55333e-20, cumulative = 5.9104e-18
Pressure gradient source: uncorrected Ubar = 0.1335, pressure gradient = 0.000120434
GAMG:  Solving for p, Initial residual = 0.0189497, Final residual = 8.88034e-07, No Iterations 38
time step continuity errors : sum local = 5.18253e-10, global = 2.24608e-20, cumulative = 5.93286e-18
Pressure gradient source: uncorrected Ubar = 0.1335, pressure gradient = 0.000119638
ExecutionTime = 167.35 s  ClockTime = 167 s

Time = 9.9

Courant Number mean: 0.73339 max: 1.27894
GAMG:  Solving for p, Initial residual = 0.100093, Final residual = 0.00073128, No Iterations 6
time step continuity errors : sum local = 4.28756e-07, global = 1.40838e-20, cumulative = 5.94694e-18
Pressure gradient source: uncorrected Ubar = 0.1335, pressure gradient = 0.000123823
GAMG:  Solving for p, Initial residual = 0.0809929, Final residual = 0.000542798, No Iterations 6
time step continuity errors : sum local = 3.21522e-07, global = -2.66223e-20, cumulative = 5.92032e-18
Pressure gradient source: uncorrected Ubar = 0.1335, pressure gradient = 0.000120471
GAMG:  Solving for p, Initial residual = 0.0189464, Final residual = 8.9418e-07, No Iterations 38
time step continuity errors : sum local = 5.22767e-10, global = 2.26167e-20, cumulative = 5.94294e-18
Pressure gradient source: uncorrected Ubar = 0.1335, pressure gradient = 0.000119674
ExecutionTime = 169.06 s  ClockTime = 169 s

Time = 10

Courant Number mean: 0.733413 max: 1.27934
GAMG:  Solving for p, Initial residual = 0.0999826, Final residual = 0.000732193, No Iterations 6
time step continuity errors : sum local = 4.29802e-07, global = 1.57268e-20, cumulative = 5.95866e-18
Pressure gradient source: uncorrected Ubar = 0.1335, pressure gradient = 0.00012387
GAMG:  Solving for p, Initial residual = 0.0810305, Final residual = 0.00054485, No Iterations 6
time step continuity errors : sum local = 3.22957e-07, global = 2.11478e-20, cumulative = 5.97981e-18
Pressure gradient source: uncorrected Ubar = 0.1335, pressure gradient = 0.000120508
GAMG:  Solving for p, Initial residual = 0.0189583, Final residual = 8.97181e-07, No Iterations 38
time step continuity errors : sum local = 5.24979e-10, global = 2.66036e-20, cumulative = 6.00642e-18
Pressure gradient source: uncorrected Ubar = 0.1335, pressure gradient = 0.00011971
ExecutionTime = 170.82 s  ClockTime = 171 s

End

kennyadapter

CPU型号：E5-2699 v4
系统：linux
OpenFOAM版本：OpenFOAM-1906
44 173.99
32 170.82
16 193.78
8 194.74
4 313.11
2 585.66
1 1146.46

为什么我的44核心会更慢呢，东岳老师？我最近在算一个200w网格的overset算例，算了半个多月了，算的还是很慢，有什么更好的解决方法吗？@东岳

kennyadapter

@netbuger 在clip中clip type选择scalar然后在下面选择CELLtype，，调整为1就行

kennyadapter

@VamosZhi 如果是2D的话是要extrudemesh一下，不过要注意下方向和起始面。我一开始也遇到过这个问题，试着改一下

flipNormals true;

这个参数，这个跟方向有关系，如果不行

sourcePatches (front);
exposedPatchName Back;

尝试改一下这两个，，换一下顺序

kennyadapter

各位老师们好，我最近使用OpenFOAM做楔形自由落体入水，OpenFOAM版本是 1906。我通过修改overInterDyMFoam例子中floatingBody案例将一个方块自由落体进入水中，发现可以计算，然后我将方块通过snappyHexMesh换为楔形，发现在计算到一半就发散了。
发散前后的速度场如图所示：

与论文的速度对比图：
我尝试使用blockMesh自己画楔形结果也是在某一处发散。
两个楔形网格如图所示：


motionSolverLibs    ("libsixDoFRigidBodyMotion.so");

dynamicFvMesh       dynamicOversetFvMesh;

solver          sixDoFRigidBodyMotion;

sixDoFRigidBodyMotionCoeffs
{

    patches         (floatingObject);
    innerDistance   100.0;
    outerDistance   101.0;

    centreOfMass    (3 1.5 1.2);
	momentOfInertia (40 921 921);

    // Density of the solid
    rhoSolid        466.7;

    // Cuboid mass
    mass           94.08;

velocity (0 0 -6.5788);
    report          on;
    accelerationRelaxation 0.6;
    accelerationDamping    0.9;

    solver
    {
        type Newmark;
    }

    constraints
    {

        /*
        fixedPoint
        {
             sixDoFRigidBodyMotionConstraint point;
             centreOfRotation (0.5 0.45 0.1);
        }
       */

        fixedLine
        {
            sixDoFRigidBodyMotionConstraint line;
            //centreOfRotation (0.5 0.45 0.1);
            direction (0 0 1);
        }
         fixedorentation
         {
            sixDoFRigidBodyMotionConstraint orientation;
             centreOfRotation (0.5 0.45 0.1);
         }
/*
        fixedAxis
        {
            sixDoFRigidBodyMotionConstraint axis;
            axis (0 1 0);
        }
        */
    }
}

这是我动网格的代码，也尝试改过

accelerationRelaxation

数值，但是效果也不明显，希望各位老师给出一些建议，非常感谢！

kennyadapter

@wwzhao 谢谢您的回复！

kennyadapter

@wwzhao 老师方便的话能加一下QQ讨论么，我的QQ号码：1219854212，非常感谢您

kennyadapter

@wwzhao 打扰您了！
alphawater：

kennyadapter

@wwzhao 非常感谢您的回复。
我的两套网格是都是通过blockMesh建立的方形区域，配置文件如下：
背景网格：

vertices
(
    (0 0.09 -1.5)
    (2.5 0.09 -1.5)
    (2.5 0.11 -1.5)
    (0 0.11 -1.5)
    (0 0.09 1)
    (2.5 0.09 1)
    (2.5 0.11 1)
    (0 0.11 1)
);

blocks
(
    hex (0 1 2 3 4 5 6 7) (500 1 500) simpleGrading (1 1 1)
);

edges
(
);

boundary
(
    // Dummy patch to trigger overset interpolation before any other
    // bcs
    oversetPatch
    {
        type overset;
        faces ();
    }
    stationaryWalls
    {
        type wall;
        faces
        (
            (0 3 2 1)
        );
    }

    inlet
    {
        type patch;
        faces
        (
            (0 4 7 3)
        );
    }
    outlet
    {
        type patch;
        faces
        (
     (2 6 5 1)
        );
    }

    frontAndBack
    {
        type empty;
        faces
        (
            (1 5 4 0)
            (3 7 6 2)
         
        );
    }


    atmosphere
    {
        type patch;
        faces
        (
            (4 5 6 7)
        );
    }
);

mergePatchPairs
(
);

子网格：

convertToMeters 1;

vertices
(
    (0.275 0.09 -0.1)
    (0.875 0.09 -0.1)
    (0.875 0.11 -0.1)
    (0.275 0.11 -0.1)
    (0.275 0.09 0.4)
    (0.875 0.09 0.4)
    (0.875 0.11 0.4)
    (0.275 0.11 0.4)
);

blocks
(
    hex (0 1 2 3 4 5 6 7) inletChannel (230 1 100) simpleGrading (1 1 1)
);

edges
(
);

boundary
(
        sides
    {
        type overset;
        faces
        (
            (0 3 2 1)
            (2 6 5 1)         
            (0 4 7 3)
            (4 5 6 7)
        );
    }

    frontAndBack
    {
        type empty;
        faces
        (
            (1 5 4 0)
            (3 7 6 2)
        );
    }

    floatingObject
    {
        type wall;
        faces ();
    }
);

在子网格用snappyHexMesh生成楔形：

将两套网格结合起来：

速度边界条件：

boundaryField
{
    #includeEtc "caseDicts/setConstraintTypes"

    inlet
    {
        type            waveVelocity;
        value           uniform (0 0 0);
    }

    outlet
    {
        type            waveVelocity;
        value           uniform (0 0 0);
    }
    stationaryWalls
    {
        type            fixedValue;
        value           uniform (0 0 0);
    }
    atmosphere
    {
        type            pressureInletOutletVelocity;
        value           uniform (0 0 0);
    }
    floatingObject
    {
        type            movingWallVelocity;
        value           uniform (0 0 0);
    }
}

压力：

boundaryField
{
    inlet
    {
        type            fixedFluxPressure;
        value           uniform 0;
    }

    outlet
    {
        type            fixedFluxPressure;
        value           uniform 0;
    }

    oversetPatch
    {
        type            overset;
    }
    stationaryWalls
    {
        type            fixedFluxPressure;
    }
    atmosphere
    {
        type            totalPressure;
        p0              uniform 0;
        U               U;
        phi             phi;
        rho             rho;
        psi             none;
        gamma           1;
        value           uniform 0;
    }
    floatingObject
    {
        type            fixedFluxPressure;
    }
    overset
    {
        patchType       overset;
        type            fixedFluxPressure;
    }
}

速度场：

压力场：

kennyadapter

@wwzhao 您好，我在用overset网格做仿真，在背景网格通过边界条件生成波浪，但是当波浪到子网格中的时候就会出现锯齿形状甚至出现很乱的流动，明明波浪还未碰到物体。请问是不是overset本身的问题，还是我网格没配置好？背景网格和子网格的网格密度要什么关系呢？搜狗截图20190625152710.png

谢谢您的解答。

kennyadapter

请问问题怎么解决的啊，效果怎么样？

kennyadapter

大家好，我在openfoam中的动网格设置遇到了一些问题，首先在motionSolverLibs 不知道填写什么，我发现填写不同的Lib里面的可用的求解器有所不同，但是也有相同的，请问相同的部分他们达到的求解效果是一样的么？
我在openfoamwiki中查到solver solidBody可以指定物体的运动。但是求解效果不好，然后solver rigidBodyMotion和sixDofRigbodyMotion我感觉是差不多的。有没有关于这些动态网格求解器的资料，想看看他们具体是解决什么样的问题的？谢谢大家。

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